Coexistent poorly-differentiated neuroendocrine cell carcinoma and non-invasive well-differentiated adenocarcinoma in tubulovillous adenoma of the rectum: report of a case

Abstract

A 74-years old man was referred to our hospital for treatment of a rectal mass. Colonoscopy revealed villous tumor covering all the lower rectal lumen. Biopsy yielded a diagnosis of adenoma. CT examination showed tumor shadows of the rectum and the liver. Pelvic MRI examination showed a 10.5×8×7 cm tumor with high signal intensity on the T2 weighted images in the rectum. Rectosigmoidectomy with lymph node dissection was performed with the diagnosis of rectal cancer that metastasized to the liver. Histological and immuno- histochemical features showed coexistent poorly-differentiated small cell neuroendocrine cell (NEC) carcinoma and non-invasive well-differentiated adenocarcinoma in tubulovillous adenoma. However the chemotherapy with FOLFOX and Bevacizumab was performed postoperatively, the patient died in cancer 3 months after surgery. Rectal poorly-differentiated NEC carcinomas are thought to be a tumor with a high malignant potential. Recently, the UICC TNM classifications of malignant tumors, 7th edition and the Guidelines for colorectal NEC tumors of European Neuroendocrine Tumor Society have been published. They would be evaluated, and effective multimodal therapy for NEC carcinomas should be established.

Mixed Adenoneuroendocrine Carcinoma in the Transverse Colon: An Infrequent Neoplasm in an Unusual Location

“…In our case, this component predominated in the resected sample, being a minority in the distant hepatic metastasis [15]. Given that we obtained a good response with the chemotherapy administered and the known response of this type of tumor to platinum and anti-angiogenic therapies (specifically with FOLFOX16 and Bevacizumab), as we can see in at least two Asiatic studies [16,17], we decided to maintain the same regimen, actually obtaining a maintained response. This situation has also been observed in other reports [18] (Figure 2).…”

Metastatic rectal neuroendocrine carcinoma presenting with treatment-refractory immune thrombocytopenia: A case report and literature review

“…[4,20] Neoplasms with substantial neuroendocrine and non-neuroendocrine components are classified as MiNENs, which contain poorly differentiated adenocarcinoma component in the colorectum. [2,4] The reported incidence and prevalence of gastrointestinal NEN has been increasing. [21][22][23] Colorectal neuroendocrine cancers are rare aggressive malignancies with a poor prognosis.…”

“…Neuroendocrine carcinomas demonstrate a high proliferation rate, as reflected by a high number of mitoses and a Ki-67 positive fraction of > 20%. [2][3][4] Colorectal neuroendocrine carcinoma (CRNEC), which originates in the hind gut, is a rare aggressive cancer accounting for less than a percent of all colorectal cancer cases; however, in some studies that included collision tumor, this figure was as high as 3.9%. [5][6][7] Patients with HGNEC may be asymptomatic and are often detected incidentally during imaging studies, endoscopy of the lower gastrointestinal tract, or biopsy.…”

Mixed Adenoneuroendocrine Carcinoma of the Colon Progressed Rapidly After Hepatic Rupture: Report of a Case

“…This patient had died just 3 months after the resection of the primary lesion, despite undergoing therapy with bevacizumab þ FOLFOX6. 12 Another report concluded that TACE using doxorubicin was effective for hepatic metastases, which occur frequently. 13 Other adjunctive medications have been suggested, including cisplatin, streptozocin, fluorouracil, and mitomycin C; however, the success rate varies between 25% and 80% and thus cannot be considered a standard line of therapy.…”